Bendyfoot has given you excellent advice.
If you can't feed raw then a grain free kibble is the best and Orijen or Acana Provincial (
www.championpetfoods.com ) are the top brands imo. They are both made by the same manufacturer at their own plant which is also a plus.
As mentioned, the food forum here has lots of information as well as these two websites ....
www.dogfoodproject.com
www.dogaware.com
If you've got more questions, just ask ....there's always someone here to help.